It might be helpful to others if you could be clearer about the stage of your education you are at, as this is clearly not 11+ entry? Forgive my confusion but the scenario you present as having happened sounds a little implausible.
Right now I'm in secondary school, but I got entered for this test by my Dad, which is not the 11+ as I'm not in Year 6. I did the 13+, passed it and now I'm 'selective' (whatever that means). Basically I'm not sure about leaving the school I go to; I know grammar school means better education but as I've said I'm doing quite well in my current school.